disc vs round shape

disc and round shape both are nouns.

Word	Noun	Adjective	Verb	Adverb
disc	Yes	No	No	No
round shape	Yes	No	No	No

As nouns, round shape is a hypernym of disc; that is, round shape is a word with a broader meaning than disc:

disc (noun)	round shape (noun)
a flat circular plate	a shape that is curved and without sharp angles
sound recording consisting of a disk with a continuous groove; used to reproduce music by rotating while a phonograph needle tracks in the groove
(computer science) a memory device consisting of a flat disk covered with a magnetic coating on which information is stored
something with a round shape resembling a flat circular plate